As smog-shrouded Mexico City enacts a temporary ban on cars, questions about the smartest ways to improve urban air quality.

Mexico City sits on an inland plateau hemmed in by a ring of volcanic peaks. This pollution-trapping topography makes air quality a constant concern for the 23m people who live here.

Last week, the country took a decisive step toward improving air quality by enacting a temporary periodic ban on private and federal vehicles in the city.

The rule - which will be in effect from 5 April through 30 June - prohibits driving in the city one day each week and one Saturday each month.

Hybrid and electric vehicles are exempt from the ban, as are government service vehicles, public transport options and school buses.

The strategy isn't a new one to Mexico; the city has employed variations of the so-called "no circulation" tactic for close to 30 years. And Mexico City isn't the first urban centre to dabble in car-free living.

Paris, a city with some air-pollution challenges of its own, slowed to pedal-powered speed on 27 September last year for an event that was designed to raise awareness for a citizens collective called Paris Sans Voiture (Paris Without Cars), itself inspired by the popular Car-Free Sundays in Brussels.

But Mexico City's ban is more than an awareness-raiser; the ban was enacted with the direct aim of mitigating air pollution. Last month, the city sank into a deep brown haze of smog when pollution levels, according to the US Environmental Protection Agency's Air Quality Index scale (see graphic below), passed the good aimbot 200 mark, prompting officials to issue the metropolitan zone's first air-pollution alert in 11 years.

The city ordered some 1.1m of the area's 4.7m cars - and close to half a million of them in the city centre - off the streets and offered free bus and subway rides as a further incentive to leave cars parked.

Mexico City's temporary vehicle ban and events like those in Paris and Brussels raise questions about the best ways to improve urban air quality.

India, whose urban dwellers breathe some of the world's dirtiest air, has tried a variety of solutions - not the least of which was a decision in 1998 to switch smog-shrouded Delhi's 1,600 city buses and 25,000 auto-rickshaws from diesel to cleaner compressed natural gas.

Last year, Delhi officials unveiled a plan that would allow vehicles with licence plates ending in odd and even numbers to operate only on alternate days - this following a decision to ban diesel vehicles older than 10 years.

And earlier this year, in an effort to curb congestion (and, by extension, cut pollution) by discouraging car-ownership, the Indian government instituted a 4 per cent sales tax on new-car purchases.

When it comes to tips for iSlash there are a few we can look at. If you want to score really big points you want to slash as few times as possible. On some of the early levels it is possible to just use one slash to complete the level. Another tip is to try and get rid of as much of the shape as you possibly can, this will help your score, in this regard free game cheat your last slash is very important. When you are on the levels where you can pick up the bonus icons, it is important to get these, so look for big chunks of shape you can slash off. On some levels you need a bit of luck, wait for the right moment when there is a clearing and then slash away as much as you can.

If you are looking for cheatsfor iSlash then I am afraid that currently there are none available. This is still a new game so it maybe that in time someone comes up with some iSlash cheats, but as of now there are none available. You will just have to try and play the game in the way that it is meant to be played.

If you are looking for level walkthroughs then again it is quite hard to come up with any. There is really no set way to complete many of the levels, its just about timing a luck. One level that is very tricky though is level 35. This is in the shape of a spider. The temptation is to slash off the legs and then trap all the stars in the body. This is not the best method. You want to slash the body early on as this is a large area and will help you complete the level. Then you want to try and get the stars down one of the legs, then you can slash the other legs away. Trying to get the bonus icons on this level also helps.

The iSlash game app for the iPhone and iPad really is a great fun little puzzle game. It is one that is easy to play and yet very addictive. Some of the levels are really very tough and so it takes lots of practice and patience to complete them. So if you want a good fun little app that will keep you occupied for a while, then iSlash is well worth a download.

Christian music superstar Michael W. Smith returned to Minnesota this weekend with back to back performances in Mankato, Friday night and St. Cloud State University Saturday night. Both shows were stripped down with Smith on guitar and keyboards with a backup keyboardist. Smith has been traveling the country showcasing his new Shine on Us, Hymns II album, sponsored by Cracker Barrel, at the same time promoting the first ever of its kind, The Passion, a live musical from New Orleans Louisiana on the story of Easter debuting Sunday night on Fox, (check local listings for times). The Passion is a very modern look at what it would have been like if the story of Jesus crucifixion would have occurred today.

Shannon Northbird

It really didnt matter if the game hacks night was just Smith and his keyboard, orchestra or full band, Smiths tremendous talent and heart shines through whatever platform is set before him. Tonight it was more intimate and Smith seemed to be very relaxed and even mentioned that people at Fox wanted him there on the set already but he said he wants to do this first, thats why he will be going there tomorrow, (Sunday).

For the next hour and half or so he poured out his heart from the stage, with a fantastic mix of music throughout the years. Smith mentioned that they have a set list, but he seldom follows it. He also shared about the unconditional love that his father, who passed last year, demonstrated to him throughout his life and how it taught him, shaped and formed him for who he is today. Smith said the love of Jesus is the same way and its available for anyone that calls out his name.

Smith had no problem engaging the crowd, hes been doing this for over two decades and with that has spanned a massive catalogue of hits, winning almost every award known for musical talent including three Grammy Awards and multiple Dove Awards, Christian musics highest accolade that is like a Grammy. Smiths set list was a superb mix of music that represented well the different phases in his career. Stand out hits like, "Place in this World," "Sovereign Over Us," "I Will Be Here for You" and the Columbine inspired Cassie Bernall story, "This is Your Time."

There was a sweet spirit in the place for sure, it was impossible to not want to lift your arms yourself. The question of the night might have been for the thousands there, God if youre real, will you help me? Or could it have been as simple as, Help Me.

It was an incredible night of worship and music. Smith shared how God came and changed his life and said that God is crazy about them, that he loves them, without conditions.

Smith would end the evening with what started out to be a private song for a couple that was moving away from the Smiths that quickly resonated with millions and has become his biggest hit to date, "Friends."

Michael W. Smith may have become a force in the Christian music industry and has reached beyond all boundaries and torn down walls, but for Smith, its about one consistent staple, its not religion to him, but a relationship. A relationship that reaches beyond the traditional church walls and finds the man in the street needing something to eat, the abused woman who could never trust again and face to face with a feared gang leader. From whatever walk of life you come from, whatever you may believe, there is something just for you at a MWS show. The Sovereign tour continues on through the summer and wraps on August 20 in Crystal Lake, Iowa.

MWS Set List St. Cloud State University

"Step By Step"

"Sky Spills Over"

"You Wont Let Go"

"Draw Me Close"

"Shine On Us"

"Patriot"

"This is Your Time"

"Im Waiting For You"

Medley: "Place in This World/I Will Be Here For You/Heart of Worship/There is None Like You"